Exposure Polaroid: Instant Photos as an Addon
Exposure Polaroid adds instant photo slides and the camera that uses them, letting you produce developed pictures on the spot. The addon is built around one device and four slide types, all made at a crafting table.
The Instant Camera
The 
Instant Camera is the core item of the addon. Its recipe combines five 
Iron Ingot, one 
Oak Button, one colorless glass pane, one 
Redstone Lamp, and one 
Crafter. The Oak Button serves as the shutter control, the Redstone Lamp provides the flash, and the Crafter supplies the internal mechanism that develops a photo immediately after it is taken.
Loading Slides
Slides are inserted directly into the Instant Camera. Right-clicking with a slide in hand loads it into the camera. Sneaking while using the camera with a slide also inserts it. Both inputs feed the same slot, so you can load a slide with a normal use or a sneak-use depending on what else you are doing at the time.
The Four Slide Types
The addon provides two black and white slides and two color slides. The difference within each pair is sensitivity: the high-sensitivity versions include 
Prismarine Crystals in their recipes, while the standard versions do not.
Instant Black and White Slide — made from two 
Bone Meal, one 
Black Dye, and three 
Paper, yielding three slides.
High-Sensitivity Instant Black and White Slide — made from one Bone Meal, one Black Dye, one Prismarine Crystals, and three Paper, yielding three slides.
Instant Color Slide — made from two 
Lapis Lazuli, one Black Dye, one 
Cyan Dye, one 
Magenta Dye, one 
Yellow Dye, and three Paper, yielding three slides.
High-Sensitivity Instant Color Slide — made from one Lapis Lazuli, one Black Dye, one Prismarine Crystals, one Cyan Dye, one Magenta Dye, one Yellow Dye, and three Paper, yielding three slides.
Reading the Recipes
Every slide recipe is shaped and produces three slides per craft, so a single round of materials goes further than it first appears. The black and white line is the cheaper of the two: it needs only Bone Meal and Black Dye alongside Paper, with Prismarine Crystals added for the high-sensitivity variant. The color line is more demanding, calling for Lapis Lazuli plus the three dye colors — Cyan Dye, Magenta Dye, and Yellow Dye — in addition to Black Dye and Paper. Upgrading a color slide to high sensitivity costs one Lapis Lazuli compared to the standard recipe's two, but adds Prismarine Crystals in its place.
The Instant Camera itself is the single most expensive craft in the addon, since it consumes five Iron Ingot plus a Redstone Lamp and a Crafter. Build the camera once, then keep it fed with slides.
A Practical Order of Operations
Start by crafting the Instant Camera, since nothing else in the addon functions without it. Gather five Iron Ingot, an Oak Button, a colorless glass pane, a Redstone Lamp, and a Crafter.
Next, pick a slide line. If you want the cheapest ongoing cost, craft Instant Black and White Slide from Bone Meal, Black Dye, and Paper. If you want color, craft Instant Color Slide from Lapis Lazuli, Black Dye, Cyan Dye, Magenta Dye, Yellow Dye, and Paper.
Once you have a stock of slides, load one into the Instant Camera by right-clicking with it, or by sneaking and using the camera. With a slide loaded, the camera is ready to take an instant photo.
If you find yourself running through slides quickly, switch to the high-sensitivity recipes. High-Sensitivity Instant Black and White Slide and High-Sensitivity Instant Color Slide both add Prismarine Crystals to their respective recipes, trading a small amount of extra material for the higher-sensitivity version of the same slide.